280 Chemical Analysis of the Atmosphere. 



it goes to confirm the views which have been here taken of the sub- 

 ject. If the fingers make a series of movements, in such sure and 

 rapid succession, it is not simply because the mind has time to de- 

 terniine and will each movement, but because it has been accustom- 

 ed so to move them. It is a matter of habit. This is the decision 

 of the great mass of mankind : and there js nothing in- the whole 

 circle of intellectual phenomena to contravene it. 



When we have arrived at habit, we have arrived apparently at the 

 ultimate fact. Every body knows that the mind is most apt to operate, 

 and operates most readily, in the way in which it has operated be- 

 fore. But the question why or how it is so, probably admits of the 

 sole answer, that it is an ordinance of the Creator. It is an ordinance 

 designed and calculated to give to idleness and vice their punishment, 

 and its reward to diligence. 



If these views are correct, the proper and philosophical definition 

 of memory is not, the recalling of ideas or images laid up in the 

 mind, or the power of doing it j nor is it even, the renewing of former 

 impressions and reflections, or the power of doing it, except in those 

 doubtful cases in which the mind itself may produce actual sensations ; 

 but it is, the acts of the mind in ways to which it has been accustomed, 

 or the force of habit urging, disposing or helping the mind in the 

 performance of customary acts. Memory is either the influence or 

 power of mental habit, or the results of that habit ; and as a neces- 

 sary consequence, the improvement of the memory mainly depends on 

 the frequency and intenseness of mental action. 



Washington, Nov. 1832. 



Art. IX. — Memoir 071 the Chemical Analysis of the Atmosphere ; 



by M. Brunner, Prof, of Chemistry at Berne. Translated for 



this Journal by Prof. Griscom. 



An examination of the chemical constitution of the atmosphere, is 

 a matter of such great importance, that we are not surprised to find 

 so many efforts have been made to bring it to the highest possible de- 

 gree of perfection. The attention of philosophers has been chiefly 

 directed to the four substances of which the atmosphere, in its ordinary 

 state, is always constituted, — to the determination of the proportions 

 of these substances with as much exactness as the state of science 

 and the accuracy of our instruments will permit. 



The azote and oxygen form the great mass of atmospheric fluid, 

 and in proportions which appear almost entirely constant, — at least 



